7 research outputs found
A catalogue of [Fe/H] determinations : 1996 edition
The Catalogue of [Fe/H] determinations has been updated and now includes 5946
determinations for 3247 stars (with 751 stars in 84 associations, clusters or
galaxies). The 700 bibliographical references are complete up to December 1995
and refer only to [Fe/H] determinations obtained from high-resolution
spectroscopic observations. The Catalogue also gives the spectral type, the
object type, the visual magnitude and colour, as well as determinations of the
effective temperature and gravity for each star, when available. In this paper,
we comment on the Catalogue, the parameters listed in it, its stellar
content,and the precautions that should be observed when using it. The full
Catalogue is only available in electronic form at the CDS or upon request
([email protected]).Comment: 7 pages (Latex, A&A style), 4 PostScript figures, to be published in
A&A Supplement Series in jul
M2000 : an astrometric catalog in the Bordeaux Carte du Ciel zone +11 degrees < {delta} < +18 degrees
During four years, systematic observations have been conducted in drift scan
mode with the Bordeaux automated meridian circle in the declination band [+11 ;
+18]. The resulting astrometric catalog includes about 2 300 000 stars down to
the magnitude limit V_M=16.3. Nearly all stars (96%) have been observed at
least 6 times, the catalog being complete down to V_M=15.4. The median internal
standard error in position is about 35 mas in the V_M magnitude range [11 ;
15], which degrades to about 50 mas when the faintest stars are considered.
M2000 provides also one band photometry with a median internal standard error
of 0.04 mag. Comparisons with the Hipparcos and bright part of Tycho-2 catalogs
have enabled to estimate external errors in position to be lower than 40 mas.
In this zone and at epoch 1998, the faint part of Tycho-2 is found to have an
accuracy of 116 mas in alpha instead of 82 mas deduced from the model-based
standard errors given in the catalog.Comment: The catalogue can be fetched directly from:
ftp://cdsarc.u-strasbg.fr/cats/I/272 or queried from:
http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=I/272 More information at :
http://www.observ.u-bordeaux.fr/~soubiran/m2000.ht
Catalogue of [Fe/H] determinations for FGK stars : 2001 edition
The catalogue presented here is a compilation of published atmospheric
parameters (Teff, logg, [Fe/H]) obtained from high resolution, high
signal-to-noise spectroscopic observations. This new edition has changed
compared to the five previous versions. It is now restricted to intermediate
and low mass stars (F, G and K stars). It contains 6354 determinations of
(Teff, logg, [Fe/H]) for 3356 stars, including 909 stars in 79 stellar systems.
The literature is complete between January 1980 and December 2000 and includes
378 references. The catalogue is made up of two tables, one for field stars and
one for stars in galactic associations, open and globular clusters and external
galaxies. The catalogue is distributed through the CDS database. Access to the
catalogue with cross-identification to other sets of data is also possible with
VizieR (Ochsenbein et al. 2000).Comment: 5 pages, 4 figures, published in A&A 373, 159. Data can be fetched
directly from: ftp://cdsarc.u-strasbg.fr/cats/III/22
42 Deposited dose measurement using bremsstrahlung X-rays
International audienc
Comparative environmental performance of artisanal and commercial feed use in Peruvian freshwater aquaculture
We used Life Cycle Assessment (LCA) to evaluate some of the environmental implications of using commercial versus artisanal feeds in Peruvian freshwater aquaculture of trout (Oncorhynchus mykiss), tilapia (Oreochromis spp.) and black pacu (Colossoma macropomum). Several scenarios believed to be representative of current Peruvian aquaculture practices were modelled, namely: production of trout in Andean lake cages; and culture of black pacu and tilapia in Amazonian and coastal lowland ponds, respectively. In general, Peruvian aquaculture is characterised by low technological intensity practices. Use of commercial aquafeeds is widespread, but artisanal feeds are frequently used in certain small-scale farms. We found that trout feeds feature higher environmental burdens than do black pacu and tilapia feeds. A similar trend is observed for production of these species. Across species, the substitution of artisanal with commercial feeds, despite improving feed conversion ratios in all cases, does not always reduce overall environmental impacts. This is due to the additional energy use and transportation requirements associated with commercial feed inputs. The substitution of artisanal feeds with commercial ones generally increases environmental impacts of the fish farming systems for the specific feeds considered, despite enhanced FCRs and economies of scale. This is due to the higher environmental impacts associated to certain feed inputs used in commercial feeds, in particular highly refined feed inputs. Consequently, in light of the importance of feeds to overall life cycle impacts of aquaculture production, the Peruvian aquafeed industry should preferentially source less refined and, in general, less environmentally burdened feed inputs (e. g. Bolivian soybean products over Brazilian, high quality over lower quality fishmeal, avoiding protein concentrates, etc.), to the extent that fish farming performance (i.e. feed conversion efficiency and cost structure) is not strongly affected. Among species, black pacu aquaculture shows the best environmental performance